Sound-producing device



April 8, 1930. w. B. POTTER SOUND PRODUCING DEVICE Filed April 12. 1928 Inventor: William B. Potter by His Attorney Patented Apr. 8, 1930 UNITED STATES PATENT OFFICE WILLIAM B. POTTER, OF SCHENECTADY, NEW YORK, ASSIGN'OIB. TOGENEBAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK SOUND-PRODUCING DEVICE Application filed April 12, 1928. Serial No. 269,519.

The weight of the paper utilized for this purpose should be as light as possible consistent with the power of the driving means, but many of the paper diaphragms heretofore provided are not stiif enough to vibrate as a whole at certain or all frequencies and consequently do not faithfully reproduce sound.

The various methods proposed in the past for eliminating sound distortion have not been altogether satisfactory. I have found that flanged rings of a suitable material attached to the cone at predetermined intervals between the apex and the edge will eliminate the undesired distortion and eflect faithful reproduction of sound even at greatly amplified driving power.

The novel features which I believe characteristic of my invention are pointed out in the appended claims. My invention it self, however, will best be understood from the following specification when considered in connection with the accompanying drawings in which Fig. 1 is a side view, partly in section, of a conical diaphragm equipped with stiffening rings, according to my invention, and Fig. 2 is an enlarged view of the section at the edge of the cone.

Referring to the drawing in detail 10 is a cone preferably made of paper. At the apex of the cone 10 a metal ferrule 11, preferably of aluminum, having attached thereto a driving rod 12, is attached. At the edge of the cone 10, a flanged ring 14 is glued to the cone.

A flange 13 is bent at such an angle that when the ring 14 is glued to the cone the flange is substantially perpendicular to the axis of the cone. The flange 13 is used to support the cone. Other flanged rings 15, having flanges 16, also substantially perpendicular to the ,by Letters Patent of the United States, is

axis, are glued or otherwise attached to the cone at intervals between the ferrule 11 and ring 14. The spacin and number of these rings depends upon t e size of the cone and upon the materials used for the cone and for the rings. The rings 14 and 15 may be a high grade cardboard known as Bristol board, but any other material having the required rigidity may be used. The tendency of the cone to distort becomes greater towards the edge, and the spacing between the flanges has therefore been so graded that the distance between rings 14 and 15 is the smallest, and that between the ferrule 11 and a ring 15 is the greatest, of the spaces used. By thus grading the spacing between the flanges maximum rlgidity is secured without unduly increasing the weight of the cone.

What I claim as new and desire to secure 1. A conical diaphragm for sound reprodlicers having a flanged ring attached to its exterior surface intermediate its edge and apex.

2. A cone speaker, having a smooth interior with circumferential stiffening means on the exterior surface between the apex and base.

3. A conical diaphragm for sound reproducers having flanged rings attached to its surface intermediate its edge and apex and spaced at unequal distances from each other.

. 4. A conical diaphragm for sound reproducers having flanged rings attached to its surface intermediate its edge and apex, the spaces between said rings being graded and the largest being nearest the apex.

'5. A sound producer including a conical diaphragm, and a plurality of flanges, attached to the exterior surface of said cone, said flanges being substantially perpendicularto the axis thereof.

6. A sound producer including a conical diaphragm and a plurality of flanges attached to and substantially perpendicular to the axis of, said cone, the spacing between said flanges being graded and arranged so that the largest space is nearest the apex. F

In witness whereof, I have hereunto'set my hand this 11th davofApriL- 1928.

' WILLIAMIB'. POTTER. 

